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arXiv · 1301.2889

HI synthesis observations of the blue compact dwarf NGC 1705

E. C. Elson·W. J. G. de Blok·R. C. Kraan-Korteweg
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Abstract

Australia Telescope Compact Array HI-line observations of the nearby dwarf galaxy NGC 1705 are presented. The data are used to trace the gravitational potential of the galaxy out to several stellar disc scale lengths. A rotation curve is derived for the system and used to generate mass models. Dark matter dominates the gravitational potential at nearly all galactocentric radii. NFW and pseudo-isothermal sphere halo parameterisations allowing for good reproductions of the observations. The models suggest NGC 1705 to have a dark matter halo that it much denser and more compact than previously thought.

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E. C. Elson, W. J. G. de Blok, R. C. Kraan-Korteweg. 2013-01-14. HI synthesis observations of the blue compact dwarf NGC 1705. https://doi.org/10.1093/mnras/sts526

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